Yellowjackets build paper nests that can grow several feet across and contain combs arranged like the floors of a building covered by papery envelopes. According to the IDNR, as many as 3,000 yellowjackets can occupy just one colony.

Nests of the German yellowjacket pop up in places like crawlspaces, attics and wall voids, while Eastern yellowjackets generally build in the ground.

Fortunately, said Chitra Rao Natalie – the newest doctor with Advanced Allergy & Asthma Associates in Crystal Lake – most people who are stung do not have serious reactions.

“Generally, they will experience redness, pain and some itching around the sting, but that is normal,” Natalie said.

It is when the swelling and redness grow larger than expected or give way to swelling and numbness of the mouth, tongue and lips that a sting can mean trouble. If these symptoms arise, the victim should go to an emergency room as soon as possible.

If you are stung by a yellowjacket, said the local doctors, wash the area with soap and water. Do not try to create a bigger wound by cutting out the stinger with a knife or other sharp object.

Patel said he has seen an increasing number of patients suffering from infections that stem from cuts rather than the yellowjacket sting itself. The doctor guessed it might be related to the down economy. More people, he said, try to go without medical treatment in order to avoid bills.

Yellowjackets do not have barbed stingers like bees, and can sting multiple times without dying as a result. If a stinger does lodge in the skin, however, do not try to dig it out, Patel said.

“Don’t create another wound by cutting or digging into your skin,” he said. Using a tweezers to take the stinger out is OK.

How to avoid a sting:

• If a few bees or wasps are flying around you, stay calm and slowly walk away from the area. Swatting insects may cause them to sting.

• Take care when drinking beverages outside. Wide, open cups are wise because you can see what’s in them.

• If a bee or wasp stings you, or many insects start to fly around, cover your mouth and nose and quickly leave the area. When a bee stings, it releases a chemical that attracts other bees. If you can, get into a building or closed vehicle.